Description


A type confusion in jsish 2.0 allows incorrect control flow during execution of the OP_NEXT opcode. When an “instanceof” expression uses an array element access as the left-hand operand inside a for-in loop, the instructions implementation leaves an additional array reference on the stack rather than consuming it during OP_INSTANCEOF. As a result, OP_NEXT interprets the array as an iterator object and reads the iterCmd function pointer from an invalid structure, potentially causing a crash or enabling code execution depending on heap layout.

Related CPE's


Vulnerable

Weaknesses


134c704f-9b21-4f2e-91b3-4a467353bcc0

Secondary

CWE-843

CVSS impact metrics


CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

9.8 · Critical

Information


Source identifier

[email protected]

Vulnerability status

Analyzed

Published

2025-12-29T14:16:01.763Z

3 weeks ago

Last modified

2025-12-31T19:04:10.750Z

3 weeks ago